Ultrasensitive Assays With A Nanoparticle-Based Photonic Crystal

Abstract

A photonic crystal-immunoassay platform wherein the periodicity of wells in an array are designed based on the leaky wave-guided modes of high refractive index material and a wavelength of excitation and/or emission of electromagnetic radiation associated with a signal used in the assay.

1 . A nanoarray comprising:
 a first substrate;
 a second substrate deposited on said first substrate, said second substrate having a high refractive index and having at least one of a waveguide mode or a leaky mode; 
 a superstrate disposed on the second substrate comprising a plurality of wells, said plurality of wells having a periodicity based on said waveguide mode or said leaky mode and one of an excitation wavelength or an emission wavelength for a signal to be measured and a nanoparticle disposed in at least one of said plurality of wells. 
   
     
     
         2 . (canceled) 
     
     
         3 . The nanoarray of  claim 1  wherein said nanoparticle comprises a fluorescent tag. 
     
     
         4 . The nanoarray of  claim 1  wherein said nanoparticle further comprises an antibody. 
     
     
         5 . The nanoarray of  claim 1  wherein said nanoparticle further comprises a bacteriophage. 
     
     
         6 . (canceled) 
     
     
         7 . The nanoarray of  claim 1  wherein the plurality of wells have a diameter of less than 100 nm. 
     
     
         8 . The nanoarray of  claim 1  wherein said plurality of wells comprise a plurality of diameters. 
     
     
         9 . The nanoarray of  claim 1  wherein said signal to be measured is an optical signal. 
     
     
         10 . The nanoarray of  claim 1  wherein said periodicitiy is based on said waveguide mode or said leaky mode, said excitation wavelength and said emission wavelength for a signal to be measured. 
     
     
         11 . The nanoarray of  claim 1  wherein said first and second substrates and superstrate comprise a photonic crystal. 
     
     
         12 . A method of constructing a nanoarray comprising:
 depositing a first substrate;   depositing a second substrate having a waveguide mode or a leaky mode on said first substrate;   depositing a superstrate on said second substrate;   determining periodicity for a plurality of nanowells to be created in said superstrate based on said waveguide mode or said leaky mode and one of an excitation wavelength or an emission wavelength for a signal to be emitted from one of the plurality of nanowells;   creating said plurality of nanowells in said superstrate, said plurality of nanowells having said determined periodicity; and   disposing a nanoparticle in one of said nanowells.   
     
     
         13 . (canceled) 
     
     
         14 . The method of  claim 12  wherein a size of said nanoparticle is determined based upon a size of at least one of said plurality of nanowells. 
     
     
         15 . The method of  claim 12  wherein said plurality of nanowells have a plurality of diameters. 
     
     
         16 . The method of  claim 12  wherein the periodicity is determined using the equation D=λm/n 2 ·cos(φ) wherein D=periodicity; λ is said wavelength; m is an order of diffraction; n 2  is a refractive index of said second substrate and Φ is an internal diffraction angle between diffracted light and a surface of the nanoarray. 
     
     
         17 . The method of  claim 16  wherein said refractive index of said second substrate is 1. 
     
     
         18 . A nanoarray comprising:
 a first substrate;   a second substrate deposited on said first substrate, said second substrate having a high refractive index and having at least one of a waveguide mode or a leaky mode;   a superstrate disposed on the second substrate comprising a plurality of wells, said plurality of wells having a periodicity based on said waveguide mode or said leaky mode and one of an excitation wavelength or an emission wavelength for a signal to be measured and a bacteriophage disposed in at least one of said plurality of wells.   
     
     
         19 . The nanoarray of  claim 18  wherein the plurality of wells have a diameter of less than 100 nm. 
     
     
         20 . The nanoarray of  claim 18  wherein said periodicitiy is based on said waveguide mode or said leaky mode, said excitation wavelength and said emission wavelength for a signal to be measured. 
     
     
         21 . The nanoarray of  claim 18  wherein said first and second substrates and said superstrate comprise a photonic crystal.